At the present time most gloves made of plastic or elastomeric materials are made either by dipping a glove form in a dispersion of the plastic to form a thin film of the plastic dispersion on the glove form, or by sewing precut patterns of plastic or non-plastic material together. Additionally, gloves made of some thermoplastic materials may be manufactured from sheets of plastic which are heat sealed rather than sewn together.
However, each of these manufacturing techniques have disadvantageous features. For example, it would be desirable to manufacture gloves from sheets of thermoplastic material such as polyethylene or polypropylene, particularly nonwoven spunbonded microporous material. Many examples of such materials are commercially available for sale; for example, nonwoven spunbonded sheeting sold under the trademark TYVEK by E. I. DuPont de Nemours & Company of Wilmington, Del., and other materials like it. Microporous polytetrafluoreothylene is also available.
Such microporous materials have pores of microscopic size, of a diameter measured only in a few microns or even fractions of a micron. Such porous material would permit a glove to "breathe" for improved comfort of the hand, while at the same time exhibiting resistance to the passage of aqueous fluids through the pores, which are hydrophobic in nature. Accordingly, such gloves would be comfortable for long-term use, since they would permit air circulation through the glove wall while resisting the passage of aqueous solutions.
At the present time, there has been no practical way to manufacture then gloves out of woven or nonwoven spunbonded thermoplastic, or microporous polytetrafluoreothylene materials except, of course, by stitching the glove together, which is impractical. Polyolefin and polyester gloves might conceivably be dip molded, making use of a proper solvent, but due to their lack of resilience, they cannot be effectively removed from the glove form on which they are made without stretch setting or tearing. Similarly, polyolefin film sheeting is heat sealed, and the heat seal often is unacceptably weak.
By this invention, a method and apparatus are provided for the manufacture of gloves, capable of processing woven or nonwoven spunbonded sheeting material (including polytetrafluoroethylene) in a thermobonding process which provided improved gloves. Thus, for the first time it becomes possible to take advantage of available microporous thermoplastic material to manufacture gloves. As a further advantage, since polyolefin thermoplastic material is much less resilient than the latices and polyvinylchloride plastics that have been used in the manufacture of typical plastic or elastic gloves, an improved design of glove is provided by this invention to give an improved hand fit. When a glove is made of polyolefin and polyester material in conventional glove shapes, the effect is unsuccessful. The hand feels the misfit in the glove in a significant way, because these materials are relatively non-resilient and thus strongly resist stretching, contrary to prior art plastic and elastic gloves.